instructions.c

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// SPDX-License-Identifier: GPL-2.0
#include <linux/compiler.h>

static struct ins_ops *powerpc__associate_instruction_ops(struct arch *arch, const char *name)
{
    int i;
    struct ins_ops *ops;

    /*
     * - Interested only if instruction starts with 'b'.
     * - Few start with 'b', but aren't branch instructions.
     */
    if (name[0] != 'b'             ||
        !strncmp(name, "bcd", 3)   ||
        !strncmp(name, "brinc", 5) ||
        !strncmp(name, "bper", 4))
        return NULL;

    ops = &jump_ops;

    i = strlen(name) - 1;
    if (i < 0)
        return NULL;

    /* ignore optional hints at the end of the instructions */
    if (name[i] == '+' || name[i] == '-')
        i--;

    if (name[i] == 'l' || (name[i] == 'a' && name[i-1] == 'l')) {
        /*
         * if the instruction ends up with 'l' or 'la', then
         * those are considered 'calls' since they update LR.
         * ... except for 'bnl' which is branch if not less than
         * and the absolute form of the same.
         */
        if (strcmp(name, "bnl") && strcmp(name, "bnl+") &&
            strcmp(name, "bnl-") && strcmp(name, "bnla") &&
            strcmp(name, "bnla+") && strcmp(name, "bnla-"))
            ops = &call_ops;
    }
    if (name[i] == 'r' && name[i-1] == 'l')
        /*
         * instructions ending with 'lr' are considered to be
         * return instructions
         */
        ops = &ret_ops;

    arch__associate_ins_ops(arch, name, ops);
    return ops;
}

static int powerpc__annotate_init(struct arch *arch, char *cpuid __maybe_unused)
{
    if (!arch->initialized) {
        arch->initialized = true;
        arch->associate_instruction_ops = powerpc__associate_instruction_ops;
        arch->objdump.comment_char      = '#';
    }

    return 0;
}